What Is the Difference Between a 38B and 40A Bra?

Two popular sizes that may catch your attention are the 38B and 40A. While they might seem similar at first glance, there are subtle differences between these bra sizes that can greatly affect the way they fit and support your bust. Understanding the variations in band and cup sizes is crucial in finding the perfect bra that not only provides comfort but also enhances your natural shape. So, let's delve deeper into the disparity between a 38B and 40A bra to unravel their unique characteristics and help you make an informed decision for your lingerie collection.

Does 38A Bra Exist?

When it comes to bra sizes, there’s often a misconception that only the more common sizes are readily available. However, contrary to popular belief, a 38A bra does indeed exist and can be found from a variety of reputable brands. These brands understand the importance of catering to a diverse range of body shapes and sizes, ensuring that everyone can find their perfect fit.

They provide a range of stylish and supportive options, allowing individuals with this size to feel both comfortable and confident throughout the day. Another well-known brand, Playtex, also offers the 38A size. With their expertise in lingerie, they provide bras that prioritize both comfort and style.

Amoena is a brand that specializes in post-mastectomy bras and also offers the 38A size. Their bras are designed with the utmost care and consideration, ensuring a comfortable and secure fit for individuals who’ve undergone breast surgery. Glamorise, a brand known for their inclusive sizing, also caters to those who wear a 38A bra. Their bras are designed to provide optimal support and lift, accommodating a range of cup sizes.

Natori is another brand that offers the 38A size, focusing on combining luxurious fabrics with exceptional craftsmanship. Each of these brands recognizes the importance of offering a variety of sizes, including the often overlooked 38A, so that everyone can find the perfect fit for their unique shape and preferences.

When it comes to bra sizes, one may wonder if there’s a 38B. Well, the answer is yes! A 38B bra is bound to provide a gorgeously generous bust size, while still maintaining a relatively average cup size. It offers the perfect balance between support and comfort, ensuring a confident and comfortable fit for those who wear it.

Is There a 38B Bra Size?

When it comes to bra sizes, there’s a wide variety of options available to accommodate different body types and bust sizes. One of the bra sizes that you can find in the market is a 38B. This size represents a gorgeously generous bust size paired with a relatively average cup size.

The band size, which is the number in front of the letter, refers to the measurement around the rib cage just below the bust. In this case, it’s 38 inches.

The cup size, denoted by the letter B, represents the difference between the bust measurement and the band measurement. This often results in a proportional and balanced look, catering to those who’ve a somewhat average-sized bust.

It offers a comfortable fit and can enhance the natural shape of the bust while providing the necessary support for everyday activities.

It’s important to note that bra sizing isn’t an exact science, and individuals may find variations in fit even within the same size. Factors such as breast shape, breast density, and personal preference can influence the fit and comfort of a bra. Therefore, it’s always advisable to try on different sizes and styles to find the one that suits you best.

This size can provide a comfortable fit, ample support, and a balanced look.

Other Common Bra Sizes and Their Corresponding Measurements

There are various bra sizes beyond the usual range that people wear. These sizes would typically fall outside the standard measurements used to determine bra size, but they’re still commonly found and worn by individuals. These alternative bra sizes may have different measurements than traditional sizes, allowing for a better fit and comfort.

Source: What size is bigger of a bra, a 38 B or 38 C?..

In the world of bra sizing, it can be confusing to navigate the different sizing systems used across countries. However, when it comes to the question of whether a 38F is the same as a 38DDD, the answer is yes. It’s important to note that sizing can vary between the US and UK, so finding the right fit might require some experimentation and understanding of the conversion chart.

Is 38F the Same as 38DDD?

When it comes to bra sizes, the sizing systems used vary depending on the country. In the United States, the most commonly used system is known as US sizes. However, in the United Kingdom, a different sizing system is used, known as UK sizes. This can often lead to confusion when trying to understand if two sizes are equivalent.

When comparing a 38DDD and a 38F, it’s important to note that the band size remains the same at 3The difference lies in the cup size. In the US sizing system, DDD represents a larger cup size compared to the F cup in the UK sizing system. Therefore, while the band size remains consistent, the cup size does vary between the two sizes.

To put it simply, a 38DDD in US sizes would be the equivalent of a 38F in UK sizes. However, it’s important to note that this equivalence only applies to these specific sizes and may not hold true across all sizes in the respective systems. It’s always recommended to consult the specific size charts provided by the brand you’re purchasing from to ensure the best fit.

It’s also worth noting that there may be slight variations in sizing between different brands, even within the same country. This is due to differences in manufacturing techniques, materials used, and individual brand preferences. Therefore, it’s always a good idea to try on bras or consult the brands sizing guides, especially when transitioning between different brands or sizing systems.

Explaining the Differences Between US and UK Bra Sizing Systems

The US and UK bra sizing systems differ in how they measure and label bra sizes. In the US, bra sizes are determined by measuring the circumference of the ribcage under the bust and the fullest part of the bust. The difference between these measurements determines the cup size. The UK system follows a similar method but uses a different label for each size. For example, a US D cup is equivalent to a UK DD cup. It’s important to keep this in mind when shopping for bras internationally to ensure a proper fit.

When it comes to finding the perfect bra size, understanding sister sizes can be incredibly helpful. If your current bra size is a 40B, your sister size down would be a 38B, while your sister size up would be a 42A. These alternative sizes can provide a more comfortable fit if necessary.

What Is 40B Bra Size Equivalent To?

The 40B bra size is typically equivalent to a 38C when using sister size charts. Sister sizes refer to the sizes that have the same cup volume but different band sizes. In this case, going down a band size to 38C would mean having a slightly tighter band but a cup size that remains the same. Similarly, going up a band size would result in a slightly looser band but the same cup volume.

These options allow for personal preference in terms of band fit while keeping the cup volume consistent.

It’s important to note that sister sizes can be helpful when fine-tuning your bra fit. However, different brands may have slight variations in sizing, so trying on various sizes and styles is recommended to ensure the best fit and comfort. Professional bra fittings can also be beneficial in finding the right bra size and style for your body shape and individual needs.

Is a 42D the Same as a 40DD?

Is a 42D the same as a 40DD? The short answer is no, they aren’t the same. While it may seem like they’re similar in size, there’s actually a difference between these two cup sizes. The number in the band size represents the measurement around your ribcage, while the letter in the cup size represents the difference between your underbust and bust measurements.

If neither your cup nor band fit properly, there are a few steps you can take to find the right size. This means if you were wearing a 42D, you could try a 40D instead. By going down a band size, the band will fit snugly around your ribcage, giving you better support.

For example, if you were wearing a 32D and it felt too small, you could try a 34D instead. Increasing the band size will give you a more comfortable fit, allowing your breasts to fully fill the cups.

It’s important to note that when you adjust the band size, the cup size will also change proportionally. So, if you go down a band size, you should try a larger cup size, and if you go up a band size, you should try a smaller cup size. This will ensure that you maintain the correct cup volume for your bust.

Finding the right bra size is all about trial and error, as everyones body is unique. It’s important to experiment with different sizes and styles until you find one that fits you perfectly. Dont be afraid to seek out professional fitting assistance if needed, as they can provide expert guidance to help you find the ideal bra size for your body shape and personal preferences.

How to Measure Your Bra Size Correctly

Finding the right bra size is essential for comfort and support. To measure your bra size correctly, follow these steps:

1. Start by wearing an unpadded bra that fits you well.
2. Take a soft measuring tape and measure around your ribcage, just below your breasts. Ensure the tape is snug but not too tight. Note down the measurement in inches.
3. To determine your band size, round the measurement to the nearest even number.
4. Next, measure around the fullest part of your bust, making sure the tape is parallel to the ground. Again, note down the measurement in inches.
5. To calculate your cup size, subtract your band size measurement from the bust measurement. Each inch difference represents a cup size. For example, if the difference is 1 inch, you’d be an A cup, 2 inches a B cup, and so on.
6. Combine your band size and cup size to find your correct bra size. For instance, if your band size is 34 inches and your cup size is 2 inches larger, you’d be a 34B.

Remember, this is just a starting point, and bra sizes can vary across brands. It’s crucial to try on various bra styles and sizes to find the perfect fit for you.


Despite the slight numerical variance, these sizes represent distinct characteristics that cater to different body types and preferences. The underband measurement, denoted by the first number, significantly affects the overall support and stability of the bra. While a 38B offers a snugger fit for individuals with smaller rib cages, a 40A accommodates a broader torso, ensuring enhanced comfort. In addition, the cup size, symbolized by the letter, complements the underband measurement by determining the appropriate depth and volume for breast support. Ultimately, selecting the perfect bra size involves a combination of measurements and personal preference to ensure a comfortable and confident fit for every individual.